This invention relates to surface lighting systems, and more particularly relates to a floodlight assembly for surface lighting of heliport pads.
The lighting of landing strips, and in particular helicopter pads, presents unique problems in that adequate lighting must be provided without interfering with the pilot's ability to control the aircraft. This means that maximum lighting must be provided with minimum of glare and distraction to the pilot of an aircraft or a helicopter. In lighting airport runways, glare is not a particular problem because the lighting is usually at right angles to the approach of the aircraft. However, in lighting heliport pads, it is necessary to provide lighting for the entire perimeter so that the pilot can distinguish the size and location of the pad. In accomplishing this, it is important to avoid not only glare which can distract the pilot, but also minimize any possible obstructions. For this reason, no present lighting system has been able to accomplish adequate lighting while being a minimum hazard to pilots.
In some cases, to provide adequate lighting, floodlights have been provided on poles, with the floodlights pointing downward spotlighting the pad. The problem with this type of lighting is that the poles themselves present a hazard to the helicopter pilot because the spotlights necessarily must be elevated considerably from the pad. In many cases, in order to provide adequate lighting, they must be of extremely high intensity so that the poles may be positioned a considerably safe distance from the pad. It is also important in illuminating these pads that perimeter lighting be provided so that the pilot can clearly determine the size and shape of the pad. With the pole-type lighting, the intensity and positioning of the lighting makes perimeter lighting difficult, as the wide area of illumination can blot out the perimeter lighting. Further, in many cases heliport pads are provided on the roofs of high-rise buildings, excluding the possibility of utilizing any type of spotlighting on poles.